Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
  • B60T10/00—Control or regulation for continuous braking making use of fluid or powdered medium, e.g. for use when descending a long slope
  • B60T10/02—Control or regulation for continuous braking making use of fluid or powdered medium, e.g. for use when descending a long slope with hydrodynamic brake
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60K—ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES
  • B60K17/00—Arrangement or mounting of transmissions in vehicles
  • B60K17/02—Arrangement or mounting of transmissions in vehicles characterised by arrangement, location, or kind of clutch
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
  • B60T1/00—Arrangements of braking elements, i.e. of those parts where braking effect occurs specially for vehicles
  • B60T1/02—Arrangements of braking elements, i.e. of those parts where braking effect occurs specially for vehicles acting by retarding wheels
  • B60T1/08—Arrangements of braking elements, i.e. of those parts where braking effect occurs specially for vehicles acting by retarding wheels using fluid or powdered medium
  • B60T1/087—Arrangements of braking elements, i.e. of those parts where braking effect occurs specially for vehicles acting by retarding wheels using fluid or powdered medium in hydrodynamic, i.e. non-positive displacement, retarders
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
  • B60T11/00—Transmitting braking action from initiating means to ultimate brake actuator without power assistance or drive or where such assistance or drive is irrelevant
  • B60T11/10—Transmitting braking action from initiating means to ultimate brake actuator without power assistance or drive or where such assistance or drive is irrelevant transmitting by fluid means, e.g. hydraulic
  • B60T11/28—Valves specially adapted therefor
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
  • F16D57/00—Liquid-resistance brakes; Brakes using the internal friction of fluids or fluid-like media, e.g. powders
  • F16D57/04—Liquid-resistance brakes; Brakes using the internal friction of fluids or fluid-like media, e.g. powders with blades causing a directed flow, e.g. Föttinger type
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
  • B60T1/00—Arrangements of braking elements, i.e. of those parts where braking effect occurs specially for vehicles
  • B60T1/02—Arrangements of braking elements, i.e. of those parts where braking effect occurs specially for vehicles acting by retarding wheels
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
  • B60W10/00—Conjoint control of vehicle sub-units of different type or different function
  • B60W10/18—Conjoint control of vehicle sub-units of different type or different function including control of braking systems
  • B60W10/196—Conjoint control of vehicle sub-units of different type or different function including control of braking systems acting within the driveline, e.g. retarders

Definitions

• the present invention relates to a hydrodynamic retarder device for a vehicle, comprising at least one shovel head stator in order to, jointly with at least one shovel head rotor, form a shovel system with a workspace for reception of an aqueous working medium, and a retarder circuit connected to the workspace, in order to control the supply of the working medium to the workspace.
• the invention also relates to a method for operation of a hydrodynamic retarder device, and a vehicle equipped with a hydrodynamic retarder device.
• a retarder device is a hydrodynamic auxiliary brake, which brakes the car's power-train with the help of the resistance exercised by a shovel system, operating an amount of liquid in a workspace.
• the braking energy absorbed by the retarder device transitions into heat energy in the liquid, which in turn is cooled down by a cooling system in the vehicle.
• the braking torque is controlled through control of a pressure prevailing in the workspace between the shovel blades belonging partly to the retarder device's stator, and partly to its rotor.
• the workspace is essentially depressurised .
• a certain drag loss is created in the retarder device, since it still rotates with the power-train. From a fuel-saving perspective it is important to keep this drag loss as small as possible.
• a method to avoid the drag loss is to mechanically disconnect the retarder device from the power-train when it is not used. This is possible with the help of a coupling, such as a synchronising clutch or a multi-plate clutch.
• the retarder device's rotor has to be accelerated quickly, and synchronised with the power-train's engine speed. This must happen within fractions of a second, and the
• acceleration torque produced must be minimised, in order to avoid uncomfortable jerks to be generated in the vehicle.
• the vehicle's ordinary coolant which typically contains a mixture of water and glycol, may be used as a working medium.
• a retarder device applying this principle is called a water retarder.
• the negative pressure generator is installed to reduce the pressure in the workspace to or below the vapour pressure for the working medium, so that the workspace is vacated of liquid working medium through the water vapour formed.
• acceleration torque at the connection is reduced in order to be level with the corresponding acceleration torque for an oil retarder device.
• Vaporisation is achieved because the pressure in the enclosed workspace, defined by the stator and the rotor, is reduced almost instantly to the vapour pressure, or to a pressure below the vapour pressure.
• the braking torque applied by the retarder device is quickly reduced to a minimum.
• a quick disconnection of the retarder device from the power-train may thus be initiated, in order to further reduce the braking torque applied by the retarder device.
• the torque is reduced sufficiently for the vehicle's system to be able, at least at an initial stage, to handle the error and/or state of emergency arisen.
• the draining valve device is advantageously designed as a safety valve, which may be made to open very quickly if an error should occur, or if the braking torque needs to be reduced quickly, e.g. to avoid tendencies to skid in a vehicle .
• the errors may be more or less temporarily sticking valves, and delays and inertia arising in control systems as well as in mechanical components.
• high standards with respect to the elements comprised in the control of the retarder device's braking torque are required.
• the valves must not stick or get stuck, since this could entail problems with interrupting the braking at transitions between a decelerated and non-decelerated state during normal operation .
• the retarder device must be such that it is able to handle the rapid processes initiated, when the skidding tendencies of the vehicle are noted by an anti- skidding system (ABS or similar) belonging to the vehicle.
• ABS anti- skidding system
• the draining valve device is advantageously designed to be optimised for its function as a safety valve with a large through flow area and brief opening times, for a fast flow of working medium flowing out from the workspace. Accordingly, the retarder device's other components do not need to be rebuilt or adapted for this function, but may instead be built and optimised for their respective functions, relating to control of braking torque emitted by the retarder device during normal operation.
• the rapidly evacuated amount of working medium from the workspace may be taken care of efficiently, so that no major pressure spikes arise in the liquid in the cooling system. Such pressure spikes would otherwise be highly
• the retarder circuit comprises a directional valve, arranged to be initiated to shut off the flow of working medium to the workspace at the initiation of the drain valve device, backfilling of the workspace is avoided in an advantageous manner.
• the negative pressure generator is advantageously arranged to reduce the pressure in the workspace to or below the vapour pressure for the working medium, so that the workspace thus is vacated of liquid working medium also at normal operation of the retarder device, to reduce
• the workspace is closed, and the pressure in the workspace is reduced to or below the vapour pressure for the working medium, and therefore the workspace is vacated of the liquid working medium.
• the workspace is thus isolated and subjected to said negative pressure, which may,
• a control valve is arranged in the control circuit downstream of the workspace, to provide for a possibility of controlling the braking torque applied by the retarder device. It is preferred to have a one-way valve arranged inside the retarder circuit in connection with the control valve, in order to ensure protection against back- flow. This one-way valve may be separate from or integrated with the control valve.
• the negative pressure generator is suitably connected with the retarder circuit downstream or upstream of the workspace, or directly with the workspace.
• the negative pressure generator is connected to the retarder circuit via an inlet valve, and to said coolant circuit via an exhaust conduit. Either, or each of the inlet conduit and the exhaust conduit, may thus need to be equipped with a one-way valve.
• the draining valve device and the negative pressure generator constitute one assembled unit since the cost, space and number of component parts in this case may be minimised.
• the negative pressure generator comprises a cylinder comprising a sealing piston, which may be moved between a first position, in which a section associated with the piston seals against a muzzle portion, placed in the cylinder, of a channel leading between the workspace and the cylinder, and a second position, in which said muzzle portion is open and the piston has been operated to generate a
• the piston is spring biased in the direction of its second position, and additionally set up to be fluid pressure activated in the direction of its first position .
• the negative pressure generator is, at preferred alternative embodiments, a negative pressure container that may be pre-charged with negative pressure or a rotation pump.
• These devices may, as in the case of a piston cylinder device, be installed to act at the required speed, so that in particular the insertion of a negative pressure container possible to pre-charge, which is constantly ready and directly switchable through a valve, entails a high degree of speed in an uncomplicated manner.
• the inlet conduit need not be equipped with a one-way valve. There is no need to arrange an outlet conduit, but it is an advantage to have such an outlet conduit, since in this case no unwanted volumetric limitation arises .
• a method according to the invention for the operation of a hydrodynamic retarder device according to the above, for connection and disconnection to a power-train in a vehicle is characterised by a flow of working medium to the workspace being controlled by way of a retarder circuit connected to the workspace, wherein the retarder circuit is connected to the vehicle's ordinary coolant circuit, and the retarder device is connected and disconnected, respectively, to/from said power-train.
• the workspace is forcibly vacated of working medium by a draining valve device arranged in the retarder circuit, and evacuated liquid working medium from the workspace is received by a negative pressure generator connected in the retarder circuit, through which the pressure in the workspace is reduced in connection with the initiation of the draining valve device.
• the clutch device may subsequently optionally be initiated to disconnect the retarder device from the power- train .
• a directional valve arranged in the retarder circuit is initiated to shut off the flow of working medium to the workspace at the initiation of the drain valve device .
• the pressure in the workspace is reduced to or below the vapour pressure for the working medium, in order to vacate the workspace of liquid working medium.
• the negative pressure generator comprises a cylinder comprising a sealing piston, which piston is moved between a first position, in which a section associated with the piston seals against a muzzle portion, placed in the cylinder, of a channel leading between the workspace and the cylinder, and a second position, in which said muzzle portion is open and the piston is operated to generate negative pressure.
• the piston is operated in the direction of its second position, suitably by a biased spring, and in the direction of its first state through pressure fluid impact.
• the invention also relates to a vehicle, comprising a retarder device according to the above.
• Fig. 1 schematically shows a commercial vehicle equipped with a retarder device according to the invention
• Figs. 2 and 3 show a principle sketch of a retarder device according to the invention according to a first
• Fig. 4 shows a principle sketch of a retarder device according to the invention according to a second embodiment
• Fig. 5 schematically shows a sequence of a method according to the invention in the form of a simple block diagram.
• the commercial vehicle 1 shown in Fig. 1 is of the type comprising an engine 2, a power-train 3 and a retarder device 4, which may be connected and disconnected.
• the basic structure of a retarder device 4 is illustrated by Figs. 2 and 3, wherein a clutch device 5 is arranged for connection and disconnection of the retarder device 4 with the vehicle's power-train 3.
• the retarder device 4 has a stator 7 and a rotor 8, which is rotatable around a shaft R.
• stator 7 and the rotor 8 form a shovel system with a workspace 6, in which a greater or lesser amount of fluid is designed to be hurled around, in order to function as a working medium in the operation of the retarder device, so that energy absorbed by the retarder device transforms into heat.
• This heat is cooled off by the vehicle's ordinary cooling system, which comprises a coolant circuit 9, a water pump 10, a front cooler 11, an expansion tank 21 and a
• a directional valve 13 inserted in the coolant circuit 9 is installed to lead coolant as a working medium to the shovel system's workspace 6, and to shut off the flow to the workspace 6, respectively.
• a retarder circuit 14 leads to an area in the workspace 6 where a lower pressure prevails during operation, and where coolant may be added as a working medium.
• the retarder circuit 14 is also, for the outlet of working medium from the
• the retarder circuit Downstream of the workspace 6, the retarder circuit passes through a control valve 15, with whose help the
• a one- way valve 16 is arranged downstream of the control valve 15, allowing for a flow of the working medium from the workspace 6, but preventing flow in the opposite direction.
• a negative pressure circuit is connected, including a negative pressure generator 19, here displayed in the form of a piston cylinder device.
• a sealing piston 31 is arranged, which may be moved between a first position (Fig. 2), in which a section 32 associated with the piston seals against a muzzle portion 33, placed in the cylinder, of a channel 34 leading between the workspace and the cylinder, and a second position (Fig. 3), in which said muzzle portion is open and the piston has been operated to generate negative pressure.
• Said section 32 associated with the piston, and the muzzle portion 33 form a draining valve device 22 for the retarder device.
• the piston 31 is spring biased in the direction of its second state with the help of a spring 35.
• the piston 31 is also arranged to be pressure fluid impacted in the direction of its first position in a cylinder chamber 37 opposite to the muzzle portion 33.
• a pressure source 36 for a gaseous medium is
• valve 23 may be shifted between a pressure conveying position (Fig. 2), where the cylinder chamber 37 is pressurised, and an emptying position (Fig. 3), where the cylinder chamber is connected with the atmosphere or similar.
• the spring 35 presses the piston 31 in a downward direction, seen in Fig. 3, to open the draining valve device 22 on the one hand, and to generate a negative pressure in the conduit 34 and thus in the workspace as set out above, on the other hand.
• the valve 23 may in turn be controlled by a system belonging to the vehicle, in order to quickly transition from the position in Fig. 2 to the position in Fig. 3 if an error arises in the retarder circuit, or if e.g. an anti-skid system belonging to the vehicle must be initiated.
• the directional valve 13 is shifted for
• Such low drag torque is achieved, on the one hand, by the retarder circuit 14 being disconnected from the cooling water circuit, and on the other, by ensuring that the
• workspace 6 substantially instantly is subjected to such a negative pressure that water vapour is formed for fast
• Two one-way valves are marked 24, which, on the one hand, partly allow for a flow to the negative power generator from the workspace and prevent a flow in the opposite
• Fig. 4 illustrates an alternative embodiment of the invention, where the negative pressure generator is a negative pressure container 25 possible to pre-charge, which may be connected to the retarder circuit via a draining valve device 26.
• the draining valve device 26 may be controlled in a manner similar to the specifications for valve 23 in Figs. 2 and 3. In such case, the one-way valve 24 is optional, but it is advantageous for the one-way valve 24 to be included.
• FIG. 5 One sequence of a method according to the invention is illustrated schematically through the block diagram in Fig. 5.
• Position 40 relates to the start of the sequence.
• Position 41 relates to normal operation of a vehicle, with the retarder device connected to the retarder circuit for retarder braking, through the directional valve's 13 settings.
• Position 42 relates to detection of a state of emergency for the vehicle, when the retarder braking torque must immediately at least be reduced.
• Position 43 relates to a shifting of the draining valve device, for substantially instant draining of the workspace of liquid working medium.
• Position 44 relates to isolation of the retarder device's workspace from the cooling water circuit
• Position 45 relates to the completion of the sequence .
• a vehicle equipped with a retarder device according to the invention therefore becomes e.g. lighter and less costly to produce, and also entails an environmental improvement
• the retarder device may
• suction devices such as a fast-acting pump device.
• a desired negative pressure generated by the negative pressure generator is in the range of or below 0.5 bar below atmospheric pressure, since the vapour pressure at normal working temperature amounts to approximately this value.
• a retarder device may comprise a shovel-equipped stator in order to, together with a shovel-equipped rotor, form the shovel system with its
• the retarder device may also comprise more than one shovel-equipped stator,

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Transportation (AREA)
• General Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Fluid Mechanics (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Transmission Of Braking Force In Braking Systems (AREA)
• Braking Arrangements (AREA)
• Hybrid Electric Vehicles (AREA)
• Lubricants (AREA)

Applications Claiming Priority (2)

Publications (3)

Family

ID=53878665

Family Applications (1)

Country Status (7)

Families Citing this family (8)

Family Cites Families (22)

• 2014
  • 2014-02-19 SE SE1450190A patent/SE538094C2/sv not_active IP Right Cessation
• 2015
  • 2015-02-13 EP EP15751648.5A patent/EP3107777B1/de not_active Not-in-force
  • 2015-02-13 WO PCT/SE2015/050172 patent/WO2015126312A1/en not_active Ceased
  • 2015-02-13 BR BR112016013994A patent/BR112016013994A2/pt not_active Application Discontinuation
  • 2015-02-13 US US15/108,007 patent/US20160325722A1/en not_active Abandoned
  • 2015-02-13 KR KR1020167025582A patent/KR101955564B1/ko not_active Expired - Fee Related
  • 2015-02-13 CN CN201580005096.3A patent/CN105939909B/zh not_active Expired - Fee Related

Also Published As

Similar Documents

Legal Events